Graduation of Aft r Gnomical bftrumenU. i<$ 
jail hand fo me reward on Mr. Ramsden, for delivering a full 
explanation of his method of making the faid engine ; which, 
in confequence, was published by order of the Board of Longi- 
tude in the year already mentioned, viz. 1 777: the deiigns 
whereof are fo full and explicit, that whoever could not under- 
Rand that defcription, fo as to enable him to make it, would be 
Unfit to undertake it on other accounts. 
From what I have faid upon the works of the different artifls 
that I have mentioned, it would feem that the art of graduation 
was brought to that degree of perfection, that nothing material 
can now be added thereto : and I fhould have been apt to have 
thought fo my lei f, if I had not happened, in the courfe of my 
life, to have had a communication made to me (under the feal of 
fecrecy) which feems to promife yet further light and affiftance 
in perfecting that important art ; and every impediment to the 
difcovery thereof being now removed, I fhall in the remainder 
of this effay give the cleared defcription thereof that I am able, 
with fuch elucidations and improvements as feem to be naturally 
pointed out by the method itfelf. 
In the autumn of the year 1741, I was firft introduced to the 
acquaintance of that then eminent artift, Mr. Henry Kindle y, 
of York, clockmaker ; — he immediately entered with me into the 
greateft freedom of communication, which founded a friendlhip 
that lafted to his death, which did not happen till the year 1771, 
at the age of 70. On the firft interview, he Ihewed me not 
only his general fet of tools, but his engine , at that time fur- 
nifhed with a dividing plate, with a great variety of numbers for 
cutting the teeth of clock wheels, &c. and alfo, for more nice 
and curious purpofes, furnifhed with a wheel of about thirteen 
inches diameter, very ftout and ftrong, and cut into 360 teeth ; 
to which was- applied an endlefs fcrew, adapted thereto. The 
D z threads 
